Astronomy: Exploring Time and Space
University of Arizona
An introduction to modern astronomy's most important questions. The four sections of the course are Planets and Life in The Universe; The Life of Stars; Galaxies and Their Environments; The History of The Universe.
More resources on Amateur Astronomy & Skywatching
stellarium.org
Stellarium is a free, open-source planetarium software that renders realistic night skies—stars, planets, constellations, and deep-sky objects—for any date, time, and location. The site offers downloads for multiple platforms and extensive documentation, tutorials, and examples to help you explore and learn astronomy.
Clear Dark Sky
Observing condition forecasts worldwide
Heavens-Above
Real-time satellite and ISS pass predictions
Cloudy Nights
Largest amateur astronomy forum for equipment reviews and advice
Amateur Podcast
The premier podcast for Amateur Radio / Ham Radio users. News, views, features, upcoming events and Amateur / Ham Radio training. ICQ Podcast is a podcast for you and including you
The Sky
The Eye On The Sky is Vermont's weather service. It is a production of the Fairbanks Museum & Planetarium and Vermont Public.